He said: Abu `Abdillah عليه السلام said: O ibn Abi Ya`foor, Allah is One, and is the only one in His oneness. He is alone in His command. So He created creatures and appointed for them that command. We are they (i.e. the aforementioned creatures), O ibn Abi Ya`foor, we are the hujaj of Allah amongst His slaves, the treasuries of His knowledge, and the ones who establish it. (al-Kafi, Volume 1, hadith 504)

He said: Abu `Abdillah عليه السلام said: Allah عز وجل created us and He made our creation the best. He formed us and made our form the best. He made us the treasuries of His heaven and His Earth. For us the tree spoke, and with our worship Allah عز وجل is worshiped – if it were not for us, Allah would not be worshiped. (al-Kafi, Volume 1, hadith 505)(sahih) (صحيح)